audacity

audacity
[ɔːˈdasɪti]
noun
[mass noun]

the willingness to take bold risks
无畏；大胆
he whistled at the sheer audacity of the plan.
听到这个大胆冒险的计划他惊奇地吹了一声口哨。
rude or disrespectful behaviour; impudence
放肆；胆大妄为
she had the audacity to suggest I'd been carrying on with him.
她竟敢暗示说我跟他关系暧昧。

语源

late Middle English : from medieval Latin audacitas, from audax, audac- 'bold' (see audacious)